Intercooler having a condensate collector

ABSTRACT

An intercooler may include a condensate collector configured to collect condensate precipitated in the intercooler. The condensate collector may be separate from the intercooler and disposed below the intercooler. The condensate collector may include at least one expansion chamber, the at least one expansion chamber arranged above an inlet and an outlet of the condensate collector during operation of the intercooler.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to the International Patent Application No. PCT/EP2016/061146, filed on May 18, 2016, and German Patent Application No. DE 10 2015 209 209.7, filed on May 20, 2015, the contents of each of which are incorporated herein by reference in their entirety.

TECHNICAL FIELD

The present invention relates to an intercooler comprising a condensate collector for collecting, in particular, condensate precipitated in the intercooler according to the preamble of claim 1. The invention further relates to an internal combustion engine comprising such an intercooler as well as a to a condensate collector.

BACKGROUND

From DE 2009 042 981 A1, a generic intercooler is known which comprises a condensate collector for collecting condensate precipitated in the intercooler. The condensate collector is connected to the internal combustion engine, that is, the manifold thereof, via a hose element so as to be able to optionally supply precipitated condensate to the combustion process.

From DE 10 2008 045 685 A1, a combustion engine arrangement is known which comprises an internal combustion engine, a charge-air compressor, an intercooler as well as a charge-air line. It is provided here that, at the lowest point of the intercooler's air channel, the intercooler has a closable condensate discharge opening which is connected to the charge-air line via a condensate discharge line. In this case, the condensate collector represents an integral part of the intercooler.

From DE 36 01 391 A1, a device for exhausting condensate oil precipitated in an air collecting tank of an intercooler is known. In order that the precipitated condensate oil can be automatically admixed to the charge air, the known device is composed of a suction pipe which extends into an air collecting tank and into a container and from which the condensate oil can be admixed again to the charge air in form of droplets and finely dispersed.

From DE 10 2009 022 986 A1, in turn, a generic intercooler for an internal combustion engine is known, comprising a plurality of substantially parallel pipes and at least one collector on the output side, each of the pipes opening into the output-side collector and a gas flow flowing into the collector and out of the collector into an outlet of the collector. Here, a structure for interacting with the gas flow is formed either on the pipes or the collector, wherein transport of a condensate to the outlet is carried out by means of the structure.

In general, it may be the case, depending on environmental conditions (temperature and relative air humidity) as well as the prevailing operating conditions, that condensate occurs in the intercooler: on the one hand, preferably at low load and low charge pressure and, on the other hand, in the case of low-pressure exhaust-gas recirculation. This may result in the charge-air-cooling operation being adversely affected, in particular at an ambient temperature below the freezing point at which the condensate can freeze. Thereby, the passage of the charge air through the intercooler can be blocked partially or entirely. Just as critical is the volume expansion of the water as it freezes, which may result in burst pipes of the intercooler. In addition, a sudden input of the entire amount of collected condensate into the internal combustion engine may in some cases cause irreparable damage to the internal combustion engine.

For this reason, it is known from the prior art to avoid condensate in the intercooler or to discharge condensate from the intercooler, for which purpose, for example, actuator-operated opening flaps are provided. Bypass lines around the intercooler are also known. Moreover, it is known from the prior to extract the condensate permanently and without any additional actuators or flaps, due to a differential pressure between an air-intake manifold and a condensate collector on the intercooler.

However, the disadvantage with the solutions known from the prior art is that either they are expensive and of complex design or they require a condensate line to be installed separately.

The present invention therefore deals with the problem of specifying, for an intercooler of the generic type, an improved or at least an alternative embodiment, which overcomes in particular the disadvantages which are known from the prior art.

According to the invention, this problem is solved by the subject matter of the independent claim 1. Advantageous embodiments form the subject matter of the dependent claims.

SUMMARY

The present invention is based on the general idea of equipping an intercooler with a specially designed condensate collector for collecting, in particular, condensate precipitated in the intercooler, wherein this specially designed condensate collector has an equalizing volume which can be utilized in the case of a freezing process of the condensate, and as a result of which damage from freezing, in particular destroying a wall of the condensate collector or of condensate collector lines, can be reliably prevented. In the case of the intercooler according to the invention, the condensate collector is formed separately from the intercooler and arranged below the same and has at least one expansion chamber which, during the operation of the intercooler, is arranged above an inlet and above an outlet of the condensate collector and for this reason only contains air and absorbs no condensate in the liquid state. For example, the at least one expansion chamber is attached on the condensate collector in a bump-like manner and due to this position, together with being arranged above the inlet and the outlet of the condensate collector, cannot be filled with liquid condensate during the normal operating state of the intercooler. Thus, the at least one expansion chamber always provides a sufficient air volume which is sufficient to provide enough space in the event of unexpected freezing of the condensate in the condensate collector so that the condensate freezing therein can expand and therefore cannot cause a bursting effect in the condensate collector affecting the functional reliability thereof. With the condensate collector designed according to the invention it is possible for the first time to design the latter in a freezeproof manner thereby reliably avoiding damages which, up to now, were caused, for example, by freezing condensate.

Suitably, the volume of the at least one expansion chamber comprises at least 10% of the volume of the condensate collector. While the water is freezing, the volume thereof increases by approx. 9%, that means that an expansion chamber which is provided in the condensate collector according to the invention and the volume of which comprises at least 10%, in particular 10-15% of the volume of the condensate collector, is sufficient to absorb the volume increase of the frozen condensate without any problems, even if the condensate collector is completely filled with condensate. Of course, it is possible here for the at least one expansion chamber to be distributed over a plurality of separate expansion chambers or to be combined within a single common expansion chamber.

In an advantageous further development of the solution according to the invention, at least one expansion chamber forms an integral part of the condensate collector. This offers the great advantage that the at least one expansion chamber can be produced together with the condensate collector, for example in a common plastic injection molding process. Such a production not only ensures a high-quality production but at the same time also a cost-effective production.

In an advantageous further development of the solution according to the invention, at least one wall of the expansion chamber is formed elastically and the expansion chamber can thus be expanded. Such an elastic formation of the wall can be achieved, for example, by means of a reduction in wall thickness so that the additional volume occurring during the freezing of the condensate can be compensated for by bulging or pressing-back of the wall. In a purely theoretical way, it is conceivable that the expansion space and/or the condensate collector are/is made from plastics or from aluminum, wherein, in particular in the region of the expansion chamber, no stiffening ribs are provided, which would impede expansion and thus an elastic backward movement of the wall during the freezing of the condensate. Similarly, a wall of the condensate collector can, of course, also be formed elastically.

In a further advantageous embodiment of the solution according to the invention, at least one expansion chamber is arranged externally with respect to the condensate collector. An expansion chamber arranged externally in such a manner can be connected to the condensate collector via a hose connection, for example. In this case, purely theoretically, the expansion chamber can also have a balloon-like structure and thus react particularly elastically to volume changes of condensate freezing in the condensate collector. The hose connection can also be implemented, for example, by means of an elastic hose, in particular a rubber hose, which also allows elastic expansion under pressure caused by freezing.

The present invention is further based on the general idea of specifying a condensate collector for a previously described intercooler which has a condensate inlet and a condensate outlet as well as at least one expansion chamber which, in operation, is arranged above the inlet and the outlet and thus is not accessible for liquid condensate. In this at least one expansion chamber there is therefore always a compressible air cushion which, while the condensate accumulated in the condensate collector is freezing, can be utilized to provide an equalizing volume for the volume increase of the frozen condensate. Such a condensate collector according to the invention can also be easily installed as a retrofit part in previously used intercoolers.

In an advantageous further development of the solution according to the invention, the condensate collector is attached, in particular welded, soldered, glued, screwed or clipped onto the air-outlet tank. This non-exhaustive list already reveals the various possibilities available for attaching the condensate collector to the air-outlet tank, namely by means of detachable connections as well as by means of non-detachable connections. In particular, screwing or clipping also makes it possible to increase the ease of maintenance and repair, since the condensate collector can be easily detached from the air-outlet tank and, for example, a condensate drain in the air-outlet tank can be cleaned. In this case, the air-outlet tank can be designed as a diffuser.

As an alternative it is also conceivable, of course, that the condensate collector is integrated into the air-outlet tank and forms an integral part of the condensate collector. This can in particular be carried out in the manner of a double bottom below the air-outlet tank or the charge air cooler. The size of the condensate collector depends primarily on the expected amount of condensate. Due to the integration of the condensate collector into the air-outlet tank, assembly of the condensate collector on the air-outlet tank can be completely dispensed with, which eliminates these assembly costs, and the intercooler can be produced overall in a more cost-effective manner.

Further important features and advantages of the invention can be gathered from the dependent claims, from the drawings and from the associated description of the figures with reference to the drawings.

It is understood that the features mentioned above, and those which are yet to be explained hereinafter, can be used not just in the combination specified in each case, but also in different combinations or on their own, without departing from the context of the present invention.

Preferred exemplary embodiments of the invention are illustrated in the drawings and will be explained in more detail in the following description, wherein like reference signs relate to like or similar, or functionally identical, components.

BRIEF DESCRIPTION OF THE DRAWINGS

In the figures, in each case schematically:

FIG. 1 shows a sectional view through an intercooler according to the invention in the region of an air-outlet tank and a condensate collector,

FIGS. 2-6 show different possible embodiments of a condensate collector according to the invention.

DETAILED DESCRIPTION

In correspondence with FIG. 1, an intercooler 1 according to the invention of an internal combustion engine 2, which is otherwise merely indicated, has a heat-exchanger block 3, an air-inlet tank, which is not shown but is located upstream of the heat-exchanger block as viewed in the flow direction 4, and an air-outlet tank 5. Also provided is a condensate collector 6 for collecting condensate 7 precipitated in the intercooler 1. The condensate 7 here runs via a discharge opening 8, which is arranged in the bottom of the air-outlet tank 5, into the condensate collector 6, which is arranged therebelow. In order for it to be possible to discharge the condensate 7 collected in the condensate collector 6, a condensate line 9 is provided, said condensate line being connected to the condensate collector 6 via an entrance 10. The condensate line 9 opens out into the air-outlet tank 5 via an exit, which is not shown, wherein a pressure difference p1>p2 prevails between the entrance 10 and the exit of the condensate line 9 during operation of the intercooler 1, which pressure difference effects a differential-pressure-induced discharge of condensate from the condensate collector 6 via the condensate line 9 into the air-outlet tank 5.

According to the invention, the condensate collector 6 now has an expansion chamber 11 which, in operation of the intercooler 1, is arranged above an inlet 12 and an outlet 13 of the condensate collector 6. Due to the at least one expansion chamber 11 and the position thereof above the inlet 12 for condensate as well as the outlet 13, this at least one expansion chamber 11 is not accessible for liquid condensate 7 during operation of the intercooler 1, but rather represents an air volume which, in the frozen state, i.e., with the condensate 7 being frozen, is capable of equalizing the accompanying volume increase thereof.

Preferably, a volume of the at least one expansion chamber 11 comprises here at least 10% of the volume of the condensate collector 6, so that the volume increase during the freezing of the condensate 7 can be absorbed without any problems. If, for example, the condensate 7 is water, the volume increase thereof during freezing is only 9%, so that with an additional volume of the at least one expansion chamber 11 of at least 10% of the volume of the entire condensate collector 6, a sufficient expansion volume is available.

In this connection, the at least one expansion chamber 11 can form an integral part of the condensate collector 6, as illustrated according to FIGS. 1 to 4, for example. As an alternative to this it is also conceivable that the at least one expansion chamber 11 is arranged externally with respect to the condensate collector 6, as is illustrated, for example, in the case of the embodiments of the condensate collector 6 according to FIGS. 5 and 6. In this case, the expansion chamber 11 is usually connected to the condensate collector 6 via a hose connection 14. The expansion chamber 11 and/or the condensate collector 6 can be made here from plastics or aluminum, wherein it can additionally be provided that at least one wall of the expansion chamber 11 and/or the condensate collector 6 is formed elastically thereby additionally allowing for a volume increase during freezing of the condensate 7.

Looking at the expansion chamber 11 according to FIG. 2, it can be seen that there is only one additional expansion chamber 11 on this condensate collector 6, while overall a plurality of expansion chambers 11 is provided in the case of the condensate collector 6 according to FIG. 1 as well as 3 and 4.

In an advantageous further development of the solution according to the invention, the condensate collector 6 is attached on the air-outlet tank 5 of the intercooler 1, for example welded, soldered, glued, screwed or clipped. As an alternative, it is also conceivable, of course, that the condensate collector 6 forms an integral part of the air-outlet tank 5 of the intercooler 1.

Irrespective of the selected embodiments of the condensate collector 6 according to the invention, the latter creates for the first time a possibility to provide a sufficient expansion volume when the condensate freezes, which makes it possible to reliably prevent damages caused by freezing. 

1. An intercooler comprising: a condensate collector configured to collect condensate precipitated in the intercooler; wherein the condensate collector is separate from the intercooler and disposed below the intercooler; and wherein the condensate collector includes at least one expansion chamber, the at least one expansion chamber arranged above an inlet and an outlet of the condensate collector during operation of the intercooler.
 2. The intercooler according to claim 1, wherein a volume of the at least one expansion chamber comprises at least 10% of a volume of the condensate collector.
 3. The intercooler according to claim 1, wherein the at least one expansion chamber defines an integral part of the condensate collector.
 4. The intercooler according to claim 1, wherein at least one wall of the expansion chamber is elastic.
 5. The intercooler according to claim 1, wherein a wall of the condensate collector is elastic.
 6. The intercooler according to claim 1, wherein the at least one expansion chamber is arranged externally with respect to the condensate collector.
 7. The intercooler according to claim 6, wherein the at least one expansion chamber is connected to the condensate collector via a hose connection.
 8. The intercooler according to claim 1, wherein at least one of the at least one expansion chamber and the condensate collector comprise plastic or aluminum.
 9. The intercooler according to claim 1, wherein the condensate collector is secured to an air-outlet tank of the intercooler, or the condensate collector defines an integral part of the air-outlet tank.
 10. A condensate collector of an intercooler, comprising: at least one expansion chamber, the at least one expansion chamber disposed above an inlet and an outlet.
 11. The condensate collector according to claim 10, wherein a volume of the at least one expansion chamber comprises at least 10% of a volume of the condensate collector.
 12. The condensate collector according to claim 10, wherein the at least one expansion chamber defines an integral part of the condensate collector, or the at least one expansion chamber is disposed externally with respect to the condensate collector.
 13. The condensate collector according to claim 10, wherein at least one of: at least one of a wall of the condensate collector and the expansion chamber are elastic; and at least one of the expansion chamber and the condensate collector comprise at least one of plastic or aluminum.
 14. An internal combustion engine comprising: a condensate collector configured to collect condensate precipitated in the intercooler; wherein the condensate collector is separate from the intercooler and disposed below the intercooler; and wherein the condensate collector includes at least one expansion chamber, the at least one expansion chamber arranged above an inlet and an outlet of the condensate collector during operation of the intercooler.
 15. The intercooler according to claim 1, wherein a volume of the at least one expansion chamber comprises 10-15% of a volume of the condensate collector.
 16. The intercooler according to claim 1, wherein the condensate collector is secured to an air-outlet tank of the intercooler.
 17. The intercooler according to claim 16, wherein the condensate collector is secured to the air-outlet tank of the intercooler via at least one of a weld, solder, glue, a screw, or a clip.
 18. The intercooler according to claim 1, wherein the condensate collector defines an integral part of an air-outlet tank.
 19. The condensate collector according to claim 10, wherein the at least one expansion chamber defines an integral part of the condensate collector.
 20. The condensate collector according to claim 10, wherein the at least one expansion chamber is disposed externally with respect to the condensate collector. 